The SIVB’s In Vitro Animal Cell Sciences Section (IVACS) held the Student and Post-Doctoral Oral Presentation Competition on Monday, June 4. This session was moderated by Dr. Addy Alt-Holland (Tufts University) and Dr. Kolla Kristjansdottir (Midwestern University). Many abstracts were submitted to be considered for this competition, and following a rigorous, peer-review process, three abstracts were selected based on their scientific merit and quality. The top three contestants delivered highly professional oral presentations, and answered numerous questions both from the judges and the SIVB members that attended the session. The panel of 9 IVACS experts that evaluated the contestants included: Dr. Mae Ciancio, Dr. Joshua Gasiorowski, and Dr. Michael J. Fay (Midwestern University), Dr. Michael Dame (University of Michigan), Dr. Brad L. Upham (Michigan State University), Dr. Barbara Doonan (New York Medical College) and Dr. John W. Harbell (JHarbell Consulting LLC). The panel also included both session moderators, Dr. Kolla Kristjansdottir and Dr. Addy Alt-Holland.

We were delighted to present certificates and monetary awards to the three contestants during the IVACS Section Business Meeting later that day. Lana Elkins from Arkansas State University won the 1st place award for his presentation “Recombinant Production and Bioactivity of Catfish Interleukin-22 as a Natural Immune Stimulant for Improved Aquaculture Fish Health.” Laura E. Knighton from The University of North Carolina at Charlotte won the 2nd place award with her presentation “The Role of Kar2/Scj1 Complex in the DNA Damage Response.” Anthony Ketner from Midwestern University won the 3rd place award for his presentation titled “Role of Retinoblastoma Gene in Maintenance of Osteoblast Function and Communication.”

The IVACS Student and Post-Doctoral Oral Presentation Competition is a unique session designed to enrich the public-speaking experience of students and Post-Doctoral candidates in a national conference. It also provides a competitive platform for them to present their research work and achievements to an expert audience, and receive invaluable feedback in a supportive environment. We highly encourage all qualified individuals to submit their research abstracts to the upcoming 2019 competition in Tampa, Florida

Submitted by the Business Office

 First Place

Recombinant Production and Bioactivity of Catfish Interleukin-22 as a Natural Immune Stimulant for Improved Aquaculture Fish Health

As the world population increases and wild caught fisheries decline, aquaculture offers an important sustainable solution in addressing this global challenge. In fact, aquaculture now provides more than half the world’s food fish. With this rapid rise in production, has come the problem of disease management. Current options are limited, and there is a need for innovative solutions. The cytokine interleukin-22 (IL-22) has emerged as a possible therapeutic target for fish and has been correlated with protection under pathogen challenge. Plant-based production systems have the potential to effectively manufacture and bring unique efficacy-enhancing features to increase the utility and value of recombinant therapeutics. Plant bioproduction offers advantages of low cost for commodity markets like aquaculture, is readily scalable, and is environmentally friendly. This project focuses on producing catfish IL-22 (cfIL-22) as a classic warm-water model. Recombinant cfIL-22 was expressed using the Agro-mediated transient tobacco production system and purified for establishing the functional activity of this potential therapeutant to trigger the fish’s immune system. As IL-22 is known to induce production of natural antimicrobials and tissue repair proteins in mammals, it may provide an alternative to antibiotics or a disease preventative at critical stages in aquaculture production. To confirm analogous activity of cfIL-22, in vitro bioassays  using a channel catfish ovary cultured cell line were established that confirmed cfIL-22’s ability to increase both cell proliferation and gene expression of select antimicrobial peptide and tissue repair markers. In addition ongoing efforts to produce and test the activity of this recombinant protein on primary gill cells will be presented.

Lana Elkins, Arkansas State University, Jonesboro, AR. In Vitro Cellular and Developmental Biology, 54:S25-26, 2018

2nd Place

The Role of Kar2/Scj1 Complex in the DNA Damage Response

Hsp70 is a well-conserved molecular chaperone involved in the folding, stabilization, and eventual degradation of many “client” proteins. Hsp70 is regulated by a suite of co-chaperone molecules that assist in Hsp70-client interaction and stimulate the intrinsic ATPase of Hsp70. While previous studies have shown the anticancer target ribonucleotide reductase (RNR) is a client of Hsp70 in yeast and mammalian cells, the regulatory co-chaperones involved remain to be determined. To identify co-chaperone(s) involved in RNR activity, 30 yeast Hsp70 co-chaperone knockout mutants were screened for sensitivity to the RNR-perturbing agent Hydroxyurea (HU). Interestingly, cells lacking the ER-resident co-chaperone Scj1 were sensitive to HU. Scj1 is an ER-based co-chaperone that binds the ER Hsp70 isoform Kar2 (homologue of BiP). Strikingly, removal of the C-terminal KDEL ER localization sequence from Scj1 only produced mild sensitivity to HU. To determine the functional role for Scj1 in mediating resistance to HU, we undertook a multicopy suppressor screen for genes that when overexpressed could rescue the HU-sensitive phenotype of of scj1∆ cells. Aside from RNR4 and SCJ1, identified GRX2, a glutaredoxin known to support RNR through hydrogen ion donation. Taken together, these findings suggest a novel indirect role for Scj1/Kar2 in the cellular response to replicative stress.

Laura Knighton, UNC Charlotte, Charlotte, NC. In Vitro Cellular and Developmental Biology, 54:S26, 2018

 3rd Place Anthony Ketner

Role of Retinoblastoma Gene in Maintenance of Osteoblast Function and Communication

Background: Osteosarcoma is a cancer of the osteoblasts and can arise with inactivation of the retinoblastoma (Rb1) tumor suppressor gene. It is known that loss of Rb1 function in mesenchymal stem cells inhibits osteoblast differentiation and predisposes them towards adipocytic lineage.  Recent studies have suggested a role for pRb1 in cell adhesion but the mechanism has not been established. Methods/Objective: As cadherin 11 and gap junctional protein, connexin43 (Cx43) play important roles in adhesion and communication in osteoblasts, we studied these proteins in MC3T3-E1 mouse calvaria osteoblast cell line. We knocked down expression of pRb1 using specific shRNA to assess the relationship between Rb1, cadherin11 and Cx43. Results: Statistically significant decreases in RNA and protein expression of cadherin11 was noted during differentiation of Rb1 deficient osteoblasts when compared to controls. Gap junctional intercellular communication was also studied using dye transfer and found to be reduced with pRb1 loss. Rb1 deficient cells had a higher steady state levels of adipocyte transcription factors and adipocyte markers when compared to control.  Interestingly no changes were observed in Cx43 gene or protein expression when comparing the two lines using qRT-PCR and Western blot, respectively. Discussion/Conclusion: These observations suggest that loss of pRb1 affects cell fate, cell adhesion and communication in osteoblasts while the exact mechanism of how communication is affected remains to be determined.

Anthony Ketner, Midwestern University, Downers Grove, IL.  In Vitro Cellular and Developmental Biology, 54:S25, 2018